1. Field of the Invention
The present invention relates to a service processing apparatus which applies selective combinations of services applicable at some point to specified data in an environment in which plural services are dynamically started or halted on plural networked computers.
2. Description of the Prior Art
With recent advances in computer networks as typified by the Internet, various services have been provided on networked servers. These services include services of numerous types, such as a retrieval service to retrieve databases based on given keywords, online shopping and ticket reservation services, and a service to translate and print given documents.
Recently, a proposal has been made to bring about new effects by not only providing a single service but also combining plural services. This enables the coupling of processing performed by services by defining an interface for exchanging data among the services. By in advance providing several services to perform basic processing and combining them, services to perform more complex processing are flexibly created.
For example, a first prior art described in Japanese Published Unexamined Patent Application No. Hei 9-218780 provides a function to design a series of document processing flows by combining services such as document printing by a printer, document input by a scanner, and document distribution by electronic mail. In an example described in the patent application, services are classified into functional categories such as document input, output, and storage, and services usable in each functional category are managed in centralized form by a database on a specific application server. Users place icons corresponding to required functional categories on a graphical user interface and connect them by links, and thereby design a processing flow. By selecting desired services from each functional category, a series of document processing such as reading documents from a specific scanner and outputting them to a specific printer can be performed.
A second prior art described in Japanese Published Unexamined Patent Application No. Hei 10-254958 provides a function to execute a combination of services provided by plural servers, based on a predetermined scenario. In an example described in the patent application, each server has a database for managing the specifications of services provided by it. Clients, based on a predetermined scenario containing a processing flow, retrieve services satisfying functional requirements constituting the processing flow from the database and invoke the obtained services in an order specified in the scenario. Thereby, for example, a series of processing such as reserving a train ticket and reserving a hotel based on the result can be performed.
In such a system that executes combinations of plural services distributed over networks, since the services operate independently of each other, not all services are always usable. Therefore, the system must manage information about a list of services usable at a given point. The information about a list of usable services must be updated according to the activation or halt of services or change of service contents.
In the first prior art, an application server managing services in centralized form periodically queries registered servers or devices such as printers and updates a database managing the services if the state of the services changes.
Moreover, if a service has been newly added, the event information is passed to the application server and the database managing the services is dynamically updated.
In the second prior art, the servers to provide services update the database for managing the service specifications according to the addition or deletion of services or change of the specifications. Moreover, in another embodiment of the second prior art, the clients manage the specifications of services in advance obtained from the servers. In this case, the servers have means to report changes of service states and the clients have means to receive the change information, and thereby update the database for managing the service specifications according to changes of service states.
Any of the above prior arts assumes routine processing such as repetitive use of preregistered combinations of services relating to specific fields. Therefore, types of services provided and combinations of the services are limited to a range predefined by a system administrator, and non-routine processing such as execution of any combination of services selected as required by users is not supported.
In the second prior art as described previously, for example, combinations of services are defined by scenarios in advance provided by a system administrator and a function for the users themselves to select necessary services and combine them is not provided.
In the first prior art, the users themselves can select and combine services only within a range based on preregistered functional categories. Accordingly, with limited freedom, the users cannot individually add new services not belonging to existing functional categories and combine them at their disposal.
However, in services over networks, there is a stronger demand for non-routine processing such as execution of free combinations of services required at a given point than for routine processing in which predetermined combinations of services are set. This is because the formats of data used in services and service contents are revised every year and new services are devised and provided one after another. For this reason, service users are required to selectively combine services applicable at the particular point to achieve their purposes.